1. Field of the Invention
The present invention relates to a water supply pipe for a steam generator.
2. Description of the Prior Art
During operation of a steam generator it frequently happens that when the water supply is cut off or reduced, a quantity of steam is admitted to the water supply pipe and it passes to the upper part of this pipe. As a result, when the water supply is returned to normal operation, the presence of the steam in the upper part of the supply pipe causes knocking in the pipe which can adversely affect the normal operation of the generator and can produce deterioration of the equipment employed.
A solution has already been proposed for preventing steam from flowing from the generator into the supply pipe and for eliminating or at least reducing the possibility of subsequent knocking in the pipe. This known solution consists of inserting an automatic one-way valve in the supply pipe in the vicinity of the generator. This know solution has disadvantages. The one-way valve, which is complicated and bulky, is an active mechanical element which requires a movement in order to carry out its operations of opening and closing the supply pipe and which is less reliable than equivalent static means. In addition, the one-way valve in point only provides comparative seal tightness to the passage of steam.